i have a 04 6.0 and a few months ago i replaced the fuel pump, filters and injectors, CAC boot and just recently all ball joints, bearings, and seals(PAIN IN THE *** btw lol) but ive always noticed that my truck has a weak start i guess youd call it. My buddies 02 7.3 starts up strong he turns the key and she starts nice and strong as opposed to mine. Mine turns over strong then sounds weak. it only happens when its a cold start like after my truck has been sitting. FICM is good and i took a voltage meter out there earlier and both batteries read between 12.5-12.7 volts does that means the batteries are fine or should i crank it and measure the voltage? Its got me stumped cant drive the truck right now because shes on jackstands waiting on her 20x12s to arrive

You need to do a load test of the batteries to see if they can deliver enough amperage not just voltage. You can have 13v but only 1 amp availble and a starter cant even turn over.

Yep, exactly right. And be sure to disconnect the cables from each battery before testing. My friends truck did this and it turns out the drivers side battery was shot. Best to replace both batteries at once, since when one gets weak the other gets overworked and fails soon thereafter.

yeah that's what i was going to do. i have a feeling the batteries are whats causing this i work at o reillys so whenever my wheels get in ill test take it to work and test them. the dates on the batteries are either from 09 or 10 if i remember correctly. any recommendations on a good set of batteries? We have people that swear by the red tops but some people say theyre the worst batteries they've ever had. anyone have any personal experience?

yeah that's what i was going to do. i have a feeling the batteries are whats causing this i work at o reillys so whenever my wheels get in ill test take it to work and test them. the dates on the batteries are either from 09 or 10 if i remember correctly. any recommendations on a good set of batteries? We have people that swear by the red tops but some people say theyre the worst batteries they've ever had. anyone have any personal experience?

Frankly, the motorcraft 850s are a preferred battery for these trucks, and they generally last 4 to 5 years. Optimas don't do very well for these trucks.

I just bought 2 motorcraft 850 batteries and my truck starts better than it ever has and when I bought the truck 3 years ago the dealer put napa legend 75 in it. I have only had the motorcraft for a week but I'm happy so far.

Register Now

In order to be able to post messages on the Ford Powerstroke Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:

Password

Please enter a password for your user account. Note that passwords are case-sensitive.

Password:

Confirm Password:

Email Address

Please enter a valid email address for yourself.

Email Address:

OR

Log-in

User Name

Password

Remember Me?

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.